problem using slice tool with a surface to cut a pad

[jonbitzen]

I'm having some difficulty using the slicing tool in the Part workbench.

My workflow is based on a YouTube video that I've been following to make a handgrip. At the point where I am currently stuck, I have made surfaces for the front and rear parts of the handgrip. In the video it shows that you can create a pad that encompasses your surfaces, and then use the surfaces with the pad and the slice apart tool to remove sections of the pad to sort of carve the handgrip.

Unfortunately, what Im finding is my surfaces dont actually cut the solid. In my exploded slice folder, what I get is slice0 which is basically the whole pad, and slice1 which looks like a new surface identical to the one I tried to use to do the cut.

I'm using FreeCAD 0.18 rev 16146 built 10.22.2019. Ive also the latest build of 0.19 and I have the same issue.

Attached is my FreeCAD file. It is post-cut, which shows the erroneous outcome.

For reference, the video I'm trying to follow is here, run forward to ~ 18:16 to see the steps where he creates the pad, and then uses the front and rear shell in to cut the pad, and obtains a solid from it.

https://www.youtube.com/watch?v=YxOLOuzOW6U&t=532s

Thanks,

jonbitzen

[chrisb]

First thing observed is, that handle-front shows errors (perhaps they are only shown in 0.19, but they exist in 0.18 too). Remove the redundant constraints!

I didn't watch the whole video but from what I saw, he uses forbidden links going out of scope: You must not use anything from inside of a body outside of it, while he uses e.g. the Pad for slicing. He should have used the whole body instead. But that is probably not the reason why your model fails: I think the author of the video was just lucky with rounding issues, but you aren't.

So I made the following changes:
- removed the redundant constraints
- made a union of the two parts of the grip
- made the block wider and gave it a height so that the face of the grip is standing out at the top and the bottom. Then slicing works.
File attached, I removed the not needed slice and the surrounding container.

[jonbitzen]

chrisb -

Thank you very much for your help. I'm going to have a go with your instructions, and see if I can replicate your work.

Thanks!

jonbitzen

[ACSUS]

I created a Box, then sliced it with a Datum Plane. However, I got an Exploded Slice and a Slice_Child0. This happens a lot. My solution to correct this is to close the file, reopen it, and try again. It works. However, I am losing all my Undo steps. Is this a known bug? Am I doing something wrong? Thanks.

OS: Windows 10 Version 2004
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24276 (Git)
Build type: Release
Branch: releases/FreeCAD-0-19
Hash: a88db11e0a908f6e38f92bfc5187b13ebe470438
Python version: 3.8.6+
Qt version: 5.15.1
Coin version: 4.0.1
OCC version: 7.5.0
Locale: English/United States (en_US)